


Unwind

by Mercy_Run



Category: Undertale (Video Game)
Genre: Ecto-Genitalia (Undertale), Fontcest, Language, M/M, Overstimulation, Praise, Praise Kink, Sensual Bondage, Shibari, Smut, light dom/sub dynamic
Language: English
Status: Completed
Published: 2017-09-17
Updated: 2017-09-17
Packaged: 2018-12-31 00:38:22
Rating: Explicit
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 1,564
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/12120762
Author URL: https://archiveofourown.org/users/Mercy_Run/pseuds/Mercy_Run
Summary: Sans has been overworking himself lately, in a constant state of anxiety from being around so many humans on the Surface.  Papyrus doesn't know why his brother is so afraid of humans but it is his more-than brotherly duty to make sure the other monster can relax.





	Unwind

**Author's Note:**

  * For [SoloShikigami](https://archiveofourown.org/users/SoloShikigami/gifts).



> A birthday gift to my sweetheart, Solo; for her birthday last year. Reposting because it got lost in the Tumblr Fic Requests, which I am splitting up anyways. 
> 
> NSFW Blog: mercy-run.tumblr.com

“papyrus…? what is all of this?” The short skeleton questioned upon returning to their shared home on the surface. The taller skeleton glanced up from the boiling pasta and took in his older brother’s state.

While Sans’ clothing was always in some state of disarray; the other’s appearance was more ragged than poorly put-together. Lack of sleep had given the monster permanent scorch marks from his magic just below his eyes. Papyrus’ expression gentled compassionately and he motioned Sans to the kitchen, who obeyed without word.

“JUST DINNER, BROTHER. DID YOU HAVE A GOOD DAY?” The taller skeleton already knew the answer he would be given but it was polite.

“‘was fine…” Sans huffed out, managing a sleepy smile for him. Papyrus turned back to the stove to hide his worried expression and rambled about his day as his thoughts centered around his sibling.

He didn’t know just how many jobs Sans was currently working, but he rarely was home.

And when he was home, Sans was sleeping.

Or…attempting sleep.

Whatever the reason, Sans had a terrible fear and mistrust of humans. He probably hadn’t realized Papyrus had picked up on it, underneath all of that passive aggressive behavior.

But violence wasn’t in Sans nature.

It wasn’t in any monster’s nature!

They had began a more than brotherly relationship shortly after Surfacing and it had been going splendidly. But lately, Sans was just too ragged to spend too much time awake, much less nurturing the intimate side of a relationship.

So Papyrus had an idea.

Turning, he plated the stuffed shells and marinara; a new dish he had learned before setting both portions at the table. This was the first time they had dinner together in a long time and the younger brother wanted it to be perfect.  
Sans’ eye-lights brightened slightly at the sight of food before offering his sibling a tired grin.

“it looks amazing, bro.” He complimented, causing Papyrus’ cheeks to flush orange in pleasure. The dinner was quiet for the most part, peaceful. The tension in Sans’ shoulders had lessened but it was still there when the taller skeleton took both of their plates to wash.

“i’m going to head to bed, bro. i-”

“Sans…” Papyrus cut in, turning around to look at his brother, who had frozen; blinking sluggishly.

“yeah, bro?”

A soft smile pulled up the skeleton’s teeth.

“Let me take charge tonight.” He insisted, using their phrase for when they played together. Sans’ sockets blinked a few times as if to clear his head before the skeleton turned his full attention to Papyrus.

“y-you don’t need to do that, paps.” The monster insisted but Papyrus was firm on this decision.

“I do. You need it and I need it. You are a mess, brother. Let me help you relax. Don’t try to explain it away, I know you haven’t been sleeping well. Your days are not fine. Let me take care of you.” He stated firmly.

Sans hesitated, clearly exhausted and deciding whether to argue it.  
But his younger brother’s concerned expression had him caving within moments. He nodded, teeth pulling up tentatively.

“okay, paps. you are in charge.” He relented and Papyrus beamed before approaching the smaller monster and picking him up, cradling his sibling close to his soul. Even in his embrace, the other’s bones were quivering with tension. He would take care of everything.

Pressing a skeleton kiss to Sans’ temple, Papyrus strode up the stairs and went into their shared bedroom. He had already prepared the room. The lights were dimmed, a lavender candle providing a relaxing aroma and he had fresh tea on the table across from their bed.

Sans eyed the soft polyester rope corded on the mattress. It wasn’t something new, but after so long; it felt like it…

“Don’t worry about a thing, brother. I will take good care of you.” Papyrus murmured and Sans smiled, appreciation flooding his soul. His younger sibling was too good to him. Especially after he had been neglecting their relationship.

…It was just so hard to care when it may all be torn away...

He was so tired.

Papyrus laid him gently on the bed before joining the smaller monster, hovering over Sans as he pressed kisses against the other’s vertebrae.

“mmm.” Sans rumbled softly, allowing the taller skeleton to pin his hands about his head. The rope was quickly and expertly tied, lacing in between his bones.

Papyrus leaned back to admire how the teal ropework looked. Sans’ face was already flushed cyan with his magic. He looked so soft and tempting like this.

“Have I ever told you how much I love you, Sans?” The taller skeleton murmured, hooking his thumbs under his sibling’s shirt and lifting it.

“e-everyday, paps…” Sans breathed, the soft glow of his soul casting a beautiful light over his delicate ribs.

“It still doesn’t feel like enough…” He responded, leaning down so his teeth pressed against Sans’ sternum, “I love you more than there are stars in the sky. You are my world. My soul belongs to you…”

Sans’ blush deepened at the words.

“paps..”

“And as much as I scolded you before, you are so hardworking. You are the furthest from lazy. You do so much for me. Have done so much for me.”

The smaller skeleton gasped Papyrus’ tongue wrapped around his floating ribs, warm and slick. His spine arched and he moaned, sockets lidding slightly.

“My precious brother… So beautiful.” The younger skeleton praised and the last of Sans’ tension faded, the smaller monster surrendering himself completely to the other.

Papyrus’ tongue licked a firm strip up the side of Sans’ ribs before he chewed carefully on the skeleton’s neck, wringing delicious sounds from his dear brother.

The other was struggling against the rope, but Papyrus knew the other skeleton inside and out. The slightest sign of fear or anxiety would make him stop.

But Sans was pliant and eager underneath his ministrations, so Papyrus took his time. He ran first his phalanges over each rib, chased by his tongue before nipping at the peak of his brother’s pelvic girdle.

“please!” Sans gasped and deciding to finally have mercy on his sibling, the taller skeleton shed the track shorts, discovering a weeping ecto-cock and clenching entrance.

“Stunning. Perfect…” Papyrus breathed and he leaned down, silencing any protest with a possessive kiss. Their tongues slid against each other as he reached between them and wrapped his hand around Sans’ girth.

“ah!”

Papyrus began pumping the cyan shaft, the pre slicking his motions. Sans bucked his hips in time with his pace, desperate noises falling from in between his teeth.

“You look so gorgeous like this, Sans… Vulnerable and willing. I adore the way you come undone.”

In response to his praising, his older brother began babbling his name mixed with pleading. Papyrus reached down with his free hand to free his erection, pumping himself in time with Sans.

“Those noises you are making are so sweet, brother.” Papyrus whispered.

“please…please…paps…inside…”

“Yes?” He slowed his pace and Sans sobbed his name, spreading his femurs.

“inside…fuck me…” Sans pleaded breathy.

Papyrus didn’t have the willpower to resist his sibling when he was in such a state. Positioning the head of his cock against the entrance below the base of Sans’ shaft, the taller skeleton gasped as he sunk slowly into his sibling.

“paps! ah! mm!”

Sans fought briefly against the rope before shuddering as Papyrus bottomed out deep inside him, cyan magic gripping the orange ecto-dick tightly, hungrily.

“So tight, Sans…so good,” Papyrus moaned before setting a slow rhythm that was driving his bound sibling crazy.

“f-faster!”

His tight control snapped and Papyrus lifted Sans’ legs, nearly folding his smaller brother in half as he began rutting. The position had his cock driving down relentlessly, their magic joined vertically as gravity caused him to sink deeper. Rougher.

The smaller monster was beyond himself, speechless and only managing primal cries of ecstasy. Papyrus himself had lost the ability to speak as he focused on driving Sans to the brink. Coherent thought slipped away and Sans screamed as he gushed blue magic around his younger brother’s cock.

Growling, Papyrus pulled out and flipped Sans onto his front, driving home in one thrust; causing his sibling to scream as his walls hugged his dick in mid-orgasm.

“papyrus! paps~!” Sans yelled as his younger brother fucked him, his walls sucking his brother’s ecto-cock in as Papyrus milked his orgasm.

His eye-lights rolled up into his skull when the other monster’s pace sped up, desperate and sloppy. A low growl reverberated in Papyrus’ ribcage, his pelvis snapping flush with Sans’ as his release flooded his brother’s passage, quickly overflowing.

He ground their dripping magic together, milking himself on Sans’ walls before thrusting purposefully until that magic seized and nearly forced him out from the force of the other monster’s release.

Sans thrashed and screamed before falling limp underneath Papyrus. Worried that he had pushed his brother too hard, the taller monster gently withdrew from Sans, their release seeping from the abused hole.

“Sans…?”

A quiet snore cut Papyrus off and he blinked in shock before smiling warmly.

His brother finally looked at peace.

It had been too long since he had last seen that expression…

“Goodnight, brother.” He whispered, pressing a kiss to Sans’ temple.


End file.
